Bordering the Bay of Riga, the Daugava River and the Ballupe River, low-key Daugavgriva is Riga's Baltic Sea gateway consisting of an industrial port and dense housing. Sand dunes separate its namesake beach from the wetlands behind, most of which are part of Piejura National Park. Daugavgriva fortress dates from the 17th-century and is open for tours during the weekend.